Relative potencies of natural estrogens on vitellogenin and choriogenin levels in the Indian freshwater spotted snakehead, <Emphasis Type="Italic">Channa punctata</Emphasis>: in vivo and in vitro studies

The relative efficacies of three natural estrogens viz., estrone (E₁), estradiol-17β (E₂) and estriol (E₃) to induce synthesis of vitellogenin (Vg) and choriogenin (Chg) were assessed in primary hepatocyte cultures of the Indian freshwater spotted snakehead, Channa punctata. Hepatocytes were isolated from the spotted snakehead liver by a non-enzymatic protocol. Optimum culture conditions were standardized for ensuring their viability and functioning. Isolated hepatocytes were cultured for 48 h for monolayer formation and then exposed to various concentrations (0.001–10 μM) of the three estrogens. Competitive homologous ELISAs, developed and validated for spotted snakehead Vg and Chg were employed to determine the amounts of these two proteins secreted into the culture medium after 48 h of incubation. The results reveal that although all the three estrogens were effective in inducing the production of Vg and Chg in a dose-dependent manner, there were differences in their relative potencies. Of three estrogens, E₁ was the least potent and could induce synthesis of Vg and Chg only at a minimum concentration of 0.5 μM; whereas significant levels of both the proteins were quantified in culture medium by exposing the hepatocytes to E₂ or E₃ even at a concentration of 0.001 μM. All three estrogens were effective in inducing synthesis of Vg and Chg in vivo also. These results suggest the possibility of employing the above in vitro experimental design to monitor the presence of estrogens/estrogen-like chemicals in natural waters, which could interfere with the estrogen receptor system of fish. This study further points to the possibility of using Chg, in addition to Vg, as a parameter for screening various chemicals for their estrogenic activity.     

Differential HSP90α expression in fish hepatocytes from polluted estuary during summer

The molecular chaperone, heat shock protein 90α (HSP90α), plays an important role in protein folding, degradation of denatured proteins and steroid activation. It is essential for the maintenance of cellular integrity and survival when induced in response to environmental, physical and chemical stresses. In the present investigation the effect of environmental stress on HSP90α expression was examined in grey mullet Mugil cephalus living in either a contaminated (Ennore) or uncontaminated (Kovalam) estuary over two seasons: Hepatocytes were isolated from grey mullet of both estuaries. Oxidative stress was determined along with HSP90α in these fish. Additionally, immunohistochemical changes were studied to confirm the HSP90α expression. Comparison of the results revealed enhanced hepatocyte oxidative stress and HSP90α expressions in fish from Ennore to a significant extent than fish from Kovalam. Also, the results showed significant seasonal variations with maximum expression observed during summer compared to the monsoon season. Overexpression of HSP90α in hepatocytes exposed to chronic environmental stress by pollutants may confer differential effects on cell survival by protecting against oxidative stress induced changes. The results also indicate that seasonal variations have significant effect on the HSP90α expression.     

Reproductive biology of the commercial sea cucumber <Emphasis Type="Italic">Holothuria spinifera</Emphasis> (Echinodermata: Holothuroidea) from Tuticorin,Tamil Nadu,India

The annual reproductive cycle of the commercial sea cucumber Holothuria spinifera was studied in Tuticorin, Tamil Nadu, India, from September 2000 to October 2001, by macroscopic and microscopic examination of gonad tubule, gonad index and histology of gametogenic stages, to determine the spawning pattern. The gonad consists of long tubules with uniform development. It does not confirm the progressive tubule recruitment model described for other holothurians. The maximum percentage of mature animals, gonad and fecundity indices, tubule length and diameter, with the observations on gonad histology, ascertained that H. spinifera had the peak gametogenic activity during September and October 2001 followed by a prolonged spawning period from November 2000–March 2001.     

Isolation, characterization and antifungal activity of major constituents of the Himalayan lichen Parmelia reticulata Tayl

Antifungal activity of hexane, ethyl acetate and methanol extracts of Parmelia reticulata was evaluated against soilborne pathogenic fungi, namely, Sclerotium rolfsii, Rhizoctonia solani, R. bataticola, Fusarium udum, Pythium aphanidermatum and P. debaryanum by poisoned food technique. Maximum antifungal activity was exhibited by hexane and ethyl acetate extracts against most of the test pathogens. Secondary metabolites, namely, (±)-isousnic acid, (±)-protolichesterinic acid, atranorin, evernyl, ethyl hematommate, ethyl orsellinate, methyl hematommate (3-formyl-2,4-dihydroxy-6-methylbenzoic acid methyl ester), 2-hydroxy-4-methoxy-3,6-dimethylbenzoic acid, 1-hydroxy-3,6-dimethoxy-8-methyl-xanthen-9-one, baeomycesic acid and salazinic acid, were isolated from the above extracts and identified by 1H NMR, 13C NMR and mass spectroscopic methods. When these metabolites were tested for antifungal activity against test pathogens, maximum antifungal activity was exhibited by (±)-protolichesterinic acid against R. solani (ED50=23.09 μg mL(-1)) and P. debaryanum (ED50=16.07 μg mL(-1)) and by atranorin against S. rolfsii (ED50=39.70 μg mL(-1)). The antifungal activity of protolichesterinic acid was found to be comparable to that of hexaconazole, a commercial fungicide.     

Preparation and Quality Evaluation of Nutritionally Enriched Jam Made from Blends of Indian Blackberry and Other Fruits

Jamun (Syzygium cumini) is a tropical, underutilized fruit which is highly perishable in nature. It is a good source of vitamin C, tannins, gallic acid and anthocyanins and its beneficial effects are mostly due to the presence of bioactive compounds (pigments and phenolic compounds) in it. Due to astringent and fibrous nature, preparation of jam from jamun pulp is quite difficult, but other fruits (apple and kiwifruit) can be incorporated in it to improve its quality. This study aims to develop jam from blends of jamun with other fruits and analyse various physico-chemical, nutritional, textural and sensory properties. It was found that physico-chemical properties of jams were not found to vary greatly, but the jamun–kiwifruit jam was found to have fairly high amount of antioxidants(46.75 ± 0.67%), tartaric acid (26.24 ± 0.02 mg/100g sample), ascorbic acid (0.08 ± 0.01 mg/100 g sample) and lactic acid (23.95 ± 0.01 mg/100g sample) and lowest amount of 5-hydroxymethyl-2-furaldehyde (0.38 ± 0.04 mg/100 g sample). Jamun jam and jamun–kiwifruit jam possessed the texture required for jam while jamun–apple jam was found to be a relatively harder gel. Jam made with jamun and kiwifruit pulp was found to have highest acceptability on the basis of sensory evaluation.     

Association of bovine KISS1 single nucleotide polymorphisms with reproductive traits in Indian Cattle

Kisspeptins, a family of neuropeptide encoded by the Kiss1 gene, have emerged as crucial regulator of fertility and reproduction by regulating the hypothalamic–pituitary–gonadal axis. The present study was aimed to identify and associate SNPs in the KISS1 gene with reproductive traits in cattle of Indian origin. DNA samples collected from 300 individual cows of three Indian dairy breeds (Gir, Kankrej and Frieswal) of cattle were used in the study. The SNPs of KISS1 gene were identified with PCR-RFLP and sequence analysis using two sets of primer pairs. A total of 5 SNPs were identified in the targeted region of which, two were selected for screening the population and association studies. The analysis revealed that genotypes of rs442633552G>A and rs42022871C>T had a significant association with dry period. The SNP rs42022871C>T also established significant role in milk production traits, and selection of TT-genotyped animals will improve the reproduction and production potential of the animals.     

Exogenous Calcium Supplementation Improves Salinity Tolerance in BRRI Dhan28; a Salt-Susceptible High-Yielding Oryza Sativa Cultivar

Journal of Crop Science and Biotechnology - Salinity is one of the most brutal abiotic stressors, commencing a great stumbling block in the way of attaining food security in Bangladesh. Cultivation...     

Application of Azotobacter enhances pond productivity and fish biomass in still water ponds

Two strains (derepressed-nitrogen fixing, Mac-27 and phosphate solubilizing, PS-21) of Azotobacter chroococcum were inoculated in fish culture ponds, singly and in combination with inorganic fertilizers (urea, single superphosphate–SSP). Physico-chemical parameters of pond waters, plankton production and fish biomass were studied. Inoculation of A. chroococcum (Mac-27) enhanced nitrogenase activity and rate of nitrogen fixation. A slight reduction in nitrogen fixation and nitrogenase activity was noticed when urea at 96 kg ha–1 y–1 was mixed with the biofertilizer (Mac-27). Inoculation of PS-21 enhanced phosphate solubilization, but Kjeldahl-nitrogen concentration values remained low in comparison with controls. On the other hand, inoculation of Azotobacter (either strain) enhanced the accumulation of ammonium-N, nitrite-N and nitrate-N. A significant (p < 0.05) reduction in dissolved oxygen (DO) concentration also took place when Azotobacter (both Mac-27 and PS-21) was inoculated in fish ponds. However, when used along with inorganic fertilizers, the reduction was not significant. The pH values were only slightly lowered when the phosphate-solubilizing strain (PS-21) of Azotobacter was inoculated. Inoculation of biofertilizer enhanced plankton production, net primary productivity and fish biomass. However, highest values in most of these parameters were noticed only in ponds that were treated with the higher doses of inorganic fertilizers (urea 192 kg and SSP 1500 kg ha–1 y–1). © Rapid Science Ltd. 1998     

Dynamic adsorption of α-pinene and linalool on silica nanoparticles for enhanced antifeedant activity against agricultural pests

The terpene compounds, α-pinene and linalool were formulated with silica nanoparticles (SNPs) by a simple immersion method and the antifeedant activity of these formulations was evaluated against two major agricultural pests, the tobacco cutworm (Spodoptera litura F.) and the castor semilooper (Achaea janata L.) in laboratory bioassays. The interaction between terpenes and SNPs, shelf-life, suspension stability as well as the bioactivity of the nanoformulations were also studied. Both these terpenes in their pure form are known to deter feeding in several lepidopterous insects. However, formulating these pure terpene compounds with nano silica enhanced their biological activity up to 25 times to S. litura. Fourier transform infrared spectroscopy analysis of these nano botanical formulations indicated the presence of hydrogen bonding between terpenes and the surface of SNPs. Transmission electron microscopy images confirmed the higher aggregation property of the SNPs. Suspension studies validated the improved shelf-life of the nano-biocomposites, while X-ray diffraction (XRD) revealed the amorphous nature of formulations and no crystalline impurities. Adsorption of α-pinene and linalool onto SNPs resulted in an effective formulation that enhanced the antifeedant potential of the individual terpenes against insects while producing longer shelf-life for the terpenes.     

Recombinant mid gut antigen (Bm95) as a vaccine against Indian Rhiphicephalus haemaphysaloides in Bos indicus cattle

In the present study, we report for the first time the efficacy of recombinant Bm95 mid gut antigen isolated from an Argentinean strain of Rhipicephalus microplus strain A in controlling the tick infestations in India. The synthetic gene for Bm95 optimized for expression in yeast was obtained and used to generate yeast transformants expressing Bm95 which was purified to apparent homogeneity. Liquid chromatography-mass spectrometry analysis of the purified protein confirmed its identity as Bm95. Vaccine was prepared by blending various concentrations of purified Bm95 with aluminium hydroxide as an adjuvant. Immunogenicity studies of the vaccine in rabbits and cattle indicated that the vaccine was highly immunogenic. The efficacy studies of the vaccine was done in cattle. Naïve Bos indicus cattle were vaccinated with the recombinant vaccine and were challenged with the larval, nymphal and adult forms of Rhiphicephalus haemaphysaloides. The vaccine protected the animals from larval, nymph and adult tick challenges with an efficacy of 98.7%, 84.6% and 78.9% respectively. The results obtained from the above studies clearly demonstrated the advantage and possibilities of the use of Bm95 in controlling R. haemaphysaloides infestations in the field.